The Fibroscan measures liver stiffness by transient elastography. Liver stiffness is directly correlated to the degree of fibrosis:

The stiffer the liver, the more the fibrosis.

Liver transplantation is the only treatment for end-stage liver failure, but in people with hepatitis C virus (HCV) infection, the virus usually recurs in the new liver soon after the operation.

The presence of significant liver fibrosis (stage F2 or greater) and portal hypertension (hepatic vein pressure gradient, or HVPG= 6mmHg) 1 year after transplantation indicates severe HCV recurrence.

In a study presented at the 43rd annual meeting of the European Association for the Study of the Liver (EASL 2008) last month in Milan, Spanish researchers assessed whether repeated liver stiffness measurements could distinguish between slow and rapid "fibrosers" during the first 12 months after transplantation.

Liver stiffness, measured by transient elastometry (FibroScan), is one of several non-invasive methods researchers are exploring as a substitute for repeat biopsies for monitoring liver disease progression.

Between February 2004 and August 2006, 66 consecutive liver transplant recipients were included in the study; 52 had hepatitis C and 14 had other causes of liver disease. Patients underwent transient elastography 3 (n=55), 6 (n=48), 9 (n=37), and 12 (n=57) months after liver transplantation. All subjects with HCV underwent liver biopsy 12 months after transplantation. HVPG was available at the same time for 47 patients.

The researchers estimated the linear function and line-slope of the 2 groups (HCV positive and negative) using a longitudinal mixed model for repeated measurements.

Results

• Among the 52 HCV-infected transplant recipients, the fibrosis stage was:

• F0-F1 (absent to mild) in 29 (56%);

• F2 (moderate) in 13 (25%);

• F3 (advanced) in 5 (9.5%);

• F4 (severe) or fibrosing cholestatic hepatitis in 5 (9.5%).

• Median liver stiffness values (in kilopascals, or kPa) at months 6, 9, and 12 were significantly higher in patients with stage F2 fibrosis (9.0, 10.4, 14.1, respectively) compared to those with higher fibrosis stages (6.7, 7.7, 6.6, respectively) (P < 0.01 at all time points).

• The figures were "practically identical" for patients with HVPG=6 or HVPG < 6mmHg 12 months after transplantation.

• The line-slope (kPa x month) in patients with stage F2 fibrosis or HVPG=6mmHg 1 year after transplantation (0.66) was significantly greater than in patients with less than F2 fibrosis or HVPG < 6 (0.03) (P<0.001) and control patients (0.001) (P < 0.001).

Conclusion

These findings, the researchers concluded, suggest 2 different speeds of liver fibrosis progression.

They added that, "early and repeated measurements of liver stiffness following hepatitis C recurrence are accurate to discriminate between rapid and slow 'fibrosers,' probably before than liver biopsy and HVPG."

Liver Unit, Hospital Clinic, Barcelona, Spain.

5/16/08

Reference
JA Carrion, X Forns, and M Navasa. Early assessment of liver stiffness identifies two different patterns of liver fibrosis progression in patients with hepatitis C recurrence after liver transplantation. 43rd annual meeting of the European Association for the Study of the Liver (EASL 2008). Milan, Italy. April 23-27, 2008.